Monkeyman, thank you very much for the details. Up til this point, I had considered a whistle to be a waste of time - I don't plan on wanting to be spotted in a SHTF kinda world. I am so small, I have little chance of defending myself especially outnumbered.. So my starting focus has been stealth-survival.. But, after learning morse code and how to make an alphabet system, I can see where a whistle could be very useful over a distance.. I also hadn't thought of using cotton balls like that. Thankyou!